Isocoma acradenia

(Greene) Greene

Erythea 2: 111. 1894.

Common names: Alkali jimmyweed
Illustrated
Basionym: Bigelowia acradenia Greene Bull. Torrey Bot. Club 10: 126. 1883 (as Bigelovia)
Synonyms: Haplopappus acradenius (Greene) S. F. Blake
Treatment appears in FNA Volume 20. Treatment on page 440.

Herbage usually glabrous, sometimes minutely hispidulous, often stipitate-glandular, often resinous. Leaf-blades oblanceolate to narrowly obovate, 20–150 mm, margins entire or toothed or lobed (teeth or lobes apically rounded-obtuse). Involucres 5–8 × 5–7 mm. Phyllary apices yellowish to greenish yellow, sometimes spinulose-aristate, usually not gland-dotted, usually with single, strongly developed, subepidermal resin pocket nearly as wide as bracts, sometimes a central pocket and 2+ smaller, lateral ones (resin pockets sometimes formed from numerous, coalesced, sessile glands). Florets 12–27; corollas 5–7 (–8) mm. Cypsela ribs not forming apical horns.

Distribution

V20-1006-distribution-map.gif

Ariz., Calif., Nev., Utah, nw Mexico

Discussion

isocoma acradenia is distinctive in its whitish stems and narrow, whitish-indurate phyllaries with an apical resin pocket (or pockets). the leaves often occur in axillary fascicles

Varieties 3 (3 in the flora).

Selected References

None.

Key

1 Leaves 50–150 mm; florets 20–27; phyllaryapices spinulose-aristate Isocoma acradenia var. bracteosa
1 Leaves 20–50 mm; florets 12–24; phyllary apices usually rounded, not spinulose, sometimes with weakly developed aristae > 2
2 Leaves usually entire, proximal rarely toothed or lobed Isocoma acradenia var. acradenia
2 Leaves all toothed to pinnatifid Isocoma acradenia var. eremophila

"thick" is not a number.

... more about "Isocoma acradenia"
not tailed +, rounded +  and obtuse +
distinct +
subequal +
scarious +
usually triangular +  and linear +
usually deltate +  and lanceolate +
spiciform +, racemiform +, paniculiform +  and corymbiform +
indeterminate +  and determinate +
Guy L. Nesom +
(Greene) Greene +
decurrent +
Bigelowia acradenia +
2 cm20 mm <br />0.02 m <br /> (15 cm150 mm <br />0.15 m <br />) +
oblanceolate +  and narrowly obovate +
linear;oblanceolate or obovate +
rugulose +  and muricate +
Alkali jimmyweed +
not 2-lipped +  and actinomorphic +
0.7 cm7 mm <br />0.007 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
subterete +, terete +  and obpyramidal +
fertile +  and bisexual +
fertile +  and bisexual +
Ariz. +, Calif. +, Nev. +, Utah +  and nw Mexico +
gland-dotted;gland-dotted +
sericeous +, tomentose +, glabrous +, villous +  and hispidulous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
indeterminate +
heterogamous +  and homogamous +
stipitate-glandular +, hispidulous +  and glabrous +
each +  and sessile +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
obconic;turbinate or campanulate +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
deltate +
dentate to pinnatifid +  and entire +
lobed +, toothed +  and entire +
2-carpellate +
persistent +
oblong +  and elliptic-lanceolate +
spinulose-aristate +
styliferous +, neuter +  and pistillate +
bearing subulate enations +, hairy +  and bristly +
concave;usually flat;conic +
exalbuminous +
Illustrated +
eglandular +  and few-branched +
resinous +
gland-dotted +
stipitate-glandular +, tomentose +, villous +, hispidulous +  and glabrous +
appendaged +  and truncate +
papillate +  and smooth +
Haplopappus acradenius +
Isocoma acradenia +
species +
goblet--shaped +
ampliate +
dark orange-resinous +
120 cm1,200 mm <br />1.2 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
20 cm200 mm <br />0.2 m <br /> (120 cm1,200 mm <br />1.2 m <br />) +
120 cm1,200 mm <br />1.2 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +